Worlds Apart - Mer Izuku x Shouto

Chapter Three

Before we begin, I would like to offer a content warning. The second part of this chapter introduces young Shouto Todoroki. If you are familiar with BNHA, you know Endeavor isn't the best father, so there will be descriptions and themes of child abuse in this chapter.

The first few days after Izuku's death and revival were excruciating in every sense of the word. The fear and pain of drowning were so vivid that he would find himself panicking and trying to hold his breath instinctively. All Might was never far from his side, and he would always try his best to comfort him and calm him when that happened.

His whole body hurt. He wasn't used to living deep in the ocean, and despite his new body, it took a lot of acclimation. Moving required muscles Izuku hadn't strengthened when he lived on land, making him sore in ways he wasn't used to. He learned that his new finlike ears were designed to withstand the pressure and be able to hear clearly in the water, but he was extra sensitive to sound, and loud noises made him startle. His eyes, while appearing unchanged, had adapted to be able to see in the dark water, and the saltwater didn't burn his eyes, but when he and All Might went closer to the surface everything felt much too bright.

Breathing hurt. He water felt thick and heavy as it flowed down his throat, and any contact on his new gills made him flinch. He had learned that the hard way when he had experimentally poked one of the thin slits that ran along his ribs. It took effort to force the water in and out of his body, and he had to consciously remember to breathe sometimes. All Might reassured him that as time passed, breathing and everything else would get easier.

Aside from the physical agony Izuku felt, he was also heartbroken. He missed his mom. He was afraid for her, thinking he was dead. He spent most of his days sobbing until he choked, and All Might would hold him, trying to calm him down, helping him until he was able to breathe again. When Midoriya wasn't terrified, distraught, or in pain was when he was asleep. His entire existence was exhausting, so he slept a lot.

While the little boy slept, All Might never left his side. Izuku regularly panicked and stopped breathing when he was awake, so All Might made sure to watch over him as he slept in case he needed help and to be there when he woke up. As the days passed, he felt fondness for the little one grow. It hurt to see him so afraid, so sad, so alone.

One of the times All Might lay near Midoriya watching over him as he slept, he began to get an idea. He had no idea if it would work, but if there was even a chance, he would try. He knew from his life as a hero that people often found themselves back at places of loss. To some, it was therapeutic. To others, it was habit. Sometimes, it was just going through the motions. From what he had seen, this practice was especially common for people who had lost a child.

The problem was that All Might was afraid of giving the child false hope of seeing his family again. Not only could he not guarantee that the boy's family could be found, Izuku couldn't breathe outside of the water yet. Light still burned his eyes. The one time he had taken the little mer above the surface to test his adjustment, he had flinched and covered his ears with his hands, complaining the sound of the crashing waves was too loud.

All Might sighed, watching closely as Midoriya slept. Even though his body was relaxed, his face looked stressed. He was slowly improving, but the change was hard on his body and his mind. Gently All Might lifted the sleeping boy into his arms. Izuku's head leaned on his arm and chest, with the end of his emerald tail falling over the other arm. Slowly so as not to wake the child, he began to swim. The light filtering through the water indicated it was near sunset.

The ascent was slow, his arms occupied with holding Midoriya. He also didn't want to disrupt Midoriya's sleep. He always got so exhausted, but falling asleep was rough as well. Eventually, All Might reached the surface, continuing to hold Midoriya below the waves so he could breathe and not be as bothered by the sound.